还原

Colloidal gold was reductively prepared by sodium citrate,sodium citrate-tannin,ascorbic acid and sodium borohydride respectively.And corresponding gold particles size,morphology,dispersion,and stability of the samples were characterized and compared.

分别采用柠檬酸钠还原法、柠檬酸钠-鞣酸还原法、抗坏血酸还原法、硼氢化钠还原法4种方法制备了粒径为十几纳米的胶体金，并对制得的纳米胶体金粒径大小、分散度、稳定性及形貌进行了表征和比较分析。

The results of batch experiments showed that the anaerobic biodegradation kinetics of 2-CNB and 4-CNB by granular sludge were follwed by first-order reaction. The nitro groups of 2-CNB and 4-CNB were more easily attacked by electron than chlorines and they were reductively biotransformed to amino groups under anaerobic conditions. The acclimated anaerobic granular sludge, which could dechlorinate 4-chloroanline to aniline, showed that it had the ability of para-dechlorinating. The anaerobic biodegradating on pathway of 2-CNB and 4-CNB were suggested as follows:AbstractIn ZVI(zero-valent iron, Fe0)-reduction system, the nitro groups of 2-CNB and 4-CNB were reductively transformed to amino groups.

2分批试验结果证明，颗粒污泥降解2-CNB和4-CNB遵循一级动力学，在厌氧条件下，CNB发生序列的硝基还原与脱氯作用，苯环上的硝基比氯原子更容易受到亲电子攻击，发生还原反应生成氨基；所获得的颗粒污泥具有对位脱氯活性，可使4-CA进一步脱氯形成苯胺。2-CNB和4-CNB厌氧降解的建议性途径为： ZVI(Zero-valentiron)对2-CNB和4-CNB的作用主要是将苯环上的硝基还原为氨基；在ZVI与污泥共还原转化体系中，ZVI对氯代硝基苯的硝基转化具有一定的促进作用，但因ZVI对中间产物的吸附特性，终产物形成速率趋慢。

In the course of reduction at about 1000℃,Fe_2O_3 and then Fe_3O_4 was almostcompletely transformed into Wüstite within a few minutes prior to the formationof metallic iron;but the reduction of Wüstite to metallic iron lasted a much lon-ger time.

在1000℃左右的还原过程中，在金属铁出现之前，在数分钟内Fe_2O_3和Fe_3O_4几乎都已全部还原成浮士体，但后者还原成金属铁的阶段，则须经历数十分钟之久，因此后一阶段便成为还原过程中控制的一步。

In the course of reduction at about 1000℃,Fe_2O_3 and then Fe_3O_4 was almostcompletely transformed into Wüstite within a few minutes prior to the formationof metallic iron;but the reduction of Wüstite to metallic iron lasted a much lon-ger time.Therefore the last stage reaction controls the whole reduction process.

在1000℃左右的还原过程中，在金属铁出现之前，在数分钟内Fe_2O_3和Fe_3O_4几乎都已全部还原成浮士体，但后者还原成金属铁的阶段，则须经历数十分钟之久，因此后一阶段便成为还原过程中控制的一步。

In 1973 the Institute of Chemical Metallurgy was engaged to carry out research on fluidizcd roasting of titaniferous iron ore containing vanadium, with the special objective of utilizing the local resources of natural gas and hydraulic electric power, by reduction of the ore with a hydrogen-rich gas followed by melting of the reduced cinder in an electric furnace in order to separate the iron from a slag rich in vanadium and titanium.

化工冶金研究所于1973年接受了&流态化焙烧还原钒钛铁矿&的任务，要求结合当地资源，用天然气还原铁精矿，用水力发电熔化焙砂，再从熔渣中提取钒和钛。我们对流态化还原的若干方面开展了试验研究，包括铁精矿还原反应数据的获得和有关分析，以及可供应用的两种流态化反应器的工程研究。第一种是气控式多层流态化床，第二种是快速流态化反应器。此外，对于流态化还原中的失流以及熔砂的渣～铁分离和从熔渣中提取钒钛，也进行了试验研究。

Reactive oxygen species causing DNA oxidative damage comes from two kinds of ways:one is from cellular normal physiological metabolism;the other is from outer environment.Redox-sensitive green fluorescent protein was expressed in Saccharomyces cerevisiae.Recombinant cells were evaluated in monitoring the changes in the redox state of living cells when challenged with toxicologically relevant metal ions NaAsO_2 or Pb(NO_3)_2 by measuring emission intensity at 510 nm with a Hitachi F6500 fluorescence spectrophotometer,roGFP expressed in yeast responded not only to typical membrane-permeant oxidants H_2O_2 and reductants DTT,but also to toxicological metal ion-induced intracellular redox changes in a dose-dependent manner.Moreover,exposure of yeast cells to NaAsO_2 or Pb(NO_3)_2 at concentrations that induced redox changes reported by roGFP caused up to 2～3 fold increases in DNA mutation frequency.This mutagenic effect was largely caused by oxidative stress since blocking the production of hydryl radicals with thiourea significantly reduced the mutation rate as well as delayed the cell death.

本文将对氧化还原状态变化敏感的绿色荧光蛋白roGFP1-R12，在酵母细胞中实现了多拷贝强表达；荧光扫描经强氧化剂H_2O_2和还原剂DTT以及环境中重金属NaAsO_2或Pb(NO_3)_2处理后的酵母细胞悬液，测定510 nm处的荧光发射强度结果显示，表达的绿色荧光蛋白对氧化还原水平敏感，且在510 nm处的荧光强度与一定的重金属浓度呈正相关，即roGFP1-R12在510nm处的荧光发射值随重金属浓度的增高而增强，从而说明重金属对细胞的毒性在一定程度上很可能是通过破坏细胞内的氧化还原平衡发生作用；同时通过该绿色荧光蛋白对胞内氧化还原状态变化的响应情况可以来实时检测环境中的重金属；遗传学的点突变频率及致死率实验数据表明，重金属能导致菌体的点突变频率和致死率升高，且活性氧的清除剂巯基脲能明显降低这种点突变和致死率，说明由重金属引发的这种点突变和致死效应在很大程度上是依赖于重金属对细胞诱导产生的氧化胁迫。

In range of 300℃～900℃, all the transition metal oxide catalysts could get high ammonia conversion, during the initial stages of the reaction, the SO〓 conversion is relatively low since the catalysts have not been sulfureted, but it increases gradually and attain constant with rising temperature and time continuance,〓 is better than other catalysts in reactivity and elemental sulfur selectivity; XRD indicates that, in the SO〓-SCR process, stable transition metal sulfide is generated which is very important to SO〓 reduction and transition metal sulfide probably is the active phase of catalyst, further the reduction of SO〓 by H〓 to H〓S is the limiting step of all process, then the activity is somewhat related to its lattice oxygen yet not so notable; XPS indicates that little sulfur on surface exists as S〓 in sulfate, showing that TiO〓 could restrain the generation of sulfate.

对于过渡金属氧化物催化剂的研究发现，在300℃～900℃范围内，不同的催化剂均可获得很高的NH〓转化率，反应初期由于催化剂还未硫化，所以SO〓的转化率较低，随着温度升高和反应时间的延续，SO〓的转化率逐渐升高并达到了稳定值；七种过渡金属氧化物中，以〓对于NH〓还原SO〓反应的活性和选择性最好；XRD结果表明在NH〓-SO〓反应后生成了稳定的硫化物相，硫化物对SO〓的还原过程具有重要作用，催化剂的活性相可能是过渡金属硫化物，而且在硫化物催化剂上进行的H〓还原SO〓生成H〓S的反应是整个过程的速率控制步骤，所以催化剂的活性与其自身的晶格氧的氧化还原能力有一定的联系，但关系不明显；XPS结果表明催化剂表面的硫大部分以过渡金属硫化物的形式存在，只生成少量的S〓，说明TiO〓催化剂能够较好的抑制硫酸盐的生成。

The experiments were carried out chemically pure ZnO and reducing agent CO to study the reduction mechanism of the process. And this reduction is important in other metallurgical processes.

为探索其还原过程的规律，首先采用化学纯ZnO进行CO还原实验，研究还原过程的有关规律，这一还原反应也是其它冶金过程中常见的和十分重要的反应。

State Key Laboratory of Pollution Control and Resources Reuse, Tongji University, Shanghai 200092, ChinaSoil and sediments are anoxic and anaerobic environment, often containing high levels of Fe due to the interaction of iron reducing bacteria with iron oxide minerals which are widely present in subsurface.

在土壤和沉积物的自然厌氧环境中，铁氧化物可被铁还原菌等微生物异化还原产生Fe，形成的Fe/铁氧化物表面结合铁系统具有还原活性，可使有机污染物还原转化。

Results of non-reducing sodium dodecyl sulphate polyacrylamide gel electrophoresis of the supernatant and aggregate precipitate formed in refolding process show that except being refolded to native egg white lysozymes, the reduced-denatured lysozymes can also form the aggregates with molecular weights being separately about 30.0 and 35.0 kD, while the reducing SDS-PAGE and the refolding results in the presence of sodium dodecyl sulphate show that these aggregates are formed chiefly through the misconnection of disulfide bonds between the reduced-denatured lysozymes, and the aggregate precipitates are formed through the non-covalent interactions between the aggregates with molecular weight being about 30.0 kD.

复性过程形成的上清和集聚体沉淀的非还原电泳结果表明，除了能复性成天然态的溶菌酶分子外，还原变性蛋白溶菌酶同时还能形成分子量分别约为30.0KD和35.0KD的蛋白溶菌酶分子集聚体；而它们的还原电泳和在SDS存在时的复性结果表明，这些集聚体主要是通过还原变性蛋白溶菌酶分子间的二硫键错配而形成，而集聚体沉淀则是通过分子量约为30.0KD的集聚体分子之间的非共价相互作用而形成。

However, as the name（read－only memory）implies, CD disks cannot be written onorchanged in any way.

然而，正如其名字所指出的那样，CD盘不能写，也不能用任何方式改变其内容。

Galvanizes steel pallet is mainly export which suits standard packing of European Union, the North America. galvanizes steel pallet is suitable to heavy rack. Pallet surface can design plate type, corrugated and the gap form, satisfies the different requirements.

镀锌钢托盘多用于出口，替代木托盘，免薰蒸，符合欧盟、北美各国对出口货物包装材料的法令要求；喷涂钢托盘适用于重载上货架之用，托盘表面根据需要制作成平板状、波纹状及间隔形式，满足不同的使用要求。